(A) pain-minimized electronics-free dual-amplified cupping transdermal delivery patch with extracellular vesicle-loaded microneedle

다국어 초록 (Multilingual Abstract)

Transdermal drug delivery offers several advantages over other routes, but the challenging barrier properties of the stratum corneum have limited its use to certain drugs, depending on drug solubility and molecular weight. Microneedles have demonstrated potential for the intratissue topical administration of large biomolecules, such as extracellular vesicles (EVs), which are known for their roles in mitigating inflammation and facilitating cellular rejuvenation. However, long needles are required to attain the appropriate penetration depth, which may often lead to discomfort, infection risks, and potential adverse effects. Here, a dual-amplification transdermal patch system utilizing an octopus-inspired cupping-driven suction cup coupled with pain-minimized dissolving short EV-loaded microneedles (≤ 300 µm) is presented. With the application of a low preload similar to that in gentle touch, stem cell-derived EVs with high molecular weight can be injected into the upper part of the skin barrier using short microneedles with minimal pain. The electronics-free dual-amplified transdermal delivery patch demonstrated significant promotion of fibroblast activity, enhanced collagen synthesis, and an overall improvement in the dermal microenvironment, underscoring its potential for anti-aging and therapeutic applications, especially for conditions requiring augmented skin regeneration and repair.

국문 초록 (Abstract)

경피 약물 전달은 다른 투여 경로에 비해 여러 가지 장점을 지니지만, 각질층의 장벽 특성으로 인해 약물 용해도와 분자량에 따라 적용 가능한 약물이 제한적이라는 한계가 있습니다. 마이크로니들(MNs)은 세포외소포(Extracellular Vesicles, EVs)과 같은 큰 생체 분자의 피부 내 국소 전달에 대한 유망한 기술로 주목받고 있습니다. 줄기세포 유래 세포외소포는 염증을 완화 및 세포 재생을 촉진 효과로 잘 알려져 있으나, 충분한 피부 침투 깊이를 확보하기 위해서는 상대적으로 긴 마이크로니들이 필요하며, 이는 통증, 감염 위험, 및 다양한 부작용을 초래할 수 있습니다. 본 연구에서는 문어의 빨판 구조에서 영감을 받은 컵-구동 흡입 장치와 통증을 최소화한 짧은 길이의 EV-탑재 마이크로니들(≤ 300 µm)을 결합한 이중 증폭 경피 패치 시스템을 제안합니다. 부드러운 접촉과 유사한 낮은 프리로드를 적용함으로써, 줄기세포 유래 세포외소포를 짧은 마이크로니들을 통해 피부 장벽의 상층부에 효과적으로 주입할 수 있으며, 이 과정에서 통증은 크게 감소합니다. 전자기기를 사용하지 않는 이 이중 증폭 경피 전달 패치는 섬유아세포 활성 촉진, 콜라겐 합성 증진 및 피부 미세 환경 개선을 유의하게 향상시켰으며, 특히 피부 재생과 회복이 필요한 상황에서 항노화 및 치료적 응용 가능성을 강조합니다.

목차 (Table of Contents)

• Chapter 1. Introduction 1
• 1.1. Background 1
• 1.1.1 Transdermal drug delivery patches 1
• 1.1.2 Microneedles 2
• 1.1.3 Extracellular Vesicles 3
• 1.1.4 Dual-amplified patch for efficient EV delivery 5
• Chapter 2. Experimental Section 8
• 2.1. Materials and methods 8
• 2.1.1 Materials 8
• 2.1.2 Fabrication of MN@EV 9
• 2.1.3 Fabrication of MN@EV/SC 9
• 2.1.4 Fabrication of octopus inspired SC 9
• 2.1.5 Fabrication of s-SC 10
• 2.1.6 Analysis of adhesion performance on the porcine skin 11
• 2.1.7 Preparation of fluorescently labeled EVs 11
• 2.1.8 Analysis of rhodamine B delivery depth on porcine skin 11
• 2.1.9 Analysis of EV delivery depth on porcine skin 12
• 2.1.10 Mouse plasma corticosterone assay 12
• 2.1.11 Cell line and animal 13
• 2.1.12 EV isolation 13
• 2.1.13 Characterization of EVs 14
• 2.1.14 Cell proliferation assay 15
• 2.1.15 Migration assay 15
• 2.1.16 Soluble collagen Assay 16
• 2.1.17 In vivo biodistributions of the EVs 16
• 2.1.18 Analysis of EVs delivery depth on porcine and mouse skin 17
• 2.1.19 Histological Analysis 17
• 2.1.20 MMP-2 ELISA assay 18
• 2.1.21. In vivo generation of soluble collagen 19
• 2.1.22 Immunohistochemistry for fibroblast biomarkers 19
• 2.1.23 Statistical analysis 20
• 2.2. Results and Discussion 21
• 2.2.1 Design and structual analysis of MN/SC patches 21
• 2.2.2 Demonstration of the MN/SC performance as EV delivery patch 29
• 2.2.3 In vivo effectiveness and prolonged release of EVs via the MN/SC patch 34
• 2.2.4 In vitro biological functions of MN@EV 39
• 2.2.5 Improvement of dermal microenvironment through MN@EV/SC in aged mice 43
• Chapter 3. Conclusion 49